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Ariyoshi, Gen; Obayashi, Hironari; Saito, Shigeru; Sasa, Toshinobu
Proceedings of 19th International Topical Meeting on Nuclear Reactor Thermal Hydraulics (NURETH-19) (Internet), 10 Pages, 2022/03
To clarify the flow characteristics of heavy liquid-metal (HLM) is important to achieve the construction of nuclear transmutation facility that utilizes HLM as a spallation target and coolant. At present, lead-bismuth eutectic (LBE) spallation target plans to be installed in Japan proton accelerator research complex (J-PARC). LBE is also selected as one of the candidate media of a spallation target and a coolant for innovative nuclear systems such as accelerator-driven system (ADS) and LBE-cooled fast reactor, due to its adequate physical/chemical properties. The characteristics of LBE flowing inside the target are usually clarified with computational fluid dynamics analysis since the measurement techniques for the HLM flow are not well established, especially for high temperature region over 450
C that is delivered from ADS's criteria. Therefore, the objective of this study is to develop measurement method for flow characteristics in the high temperature LBE. A miniature electro-magnet is introduced to electro-magnetic probe to overcome the limitation caused by a curie temperature of permanent magnet. To evaluate performance of the new probe, experimental apparatus equipping annular rotating vessel were also manufactured. The new probe was applied to high temperature LBE up to 480C. As a result, proportional induced voltage to the rotation speed of LBE were clearly observed, where excitation currents of the miniature electro-magnet were 0.2 A or 1 A. In this paper, configuration and performance of the newly developed electro-magnet probe to the high temperature LBE will be presented.
Sasa, Toshinobu
Kasokuki, 18(4), p.233 - 240, 2022/01
Lead bismuth eutectic alloy (LBE) is a promising option as a spallation target for accelerator-driven transmutation systems (ADS) to reduce the radiological toxicity from long-lived radioactive waste. LBE is a heavy metal and has suitable characteristics both as a spallation target and as a coolant for transmutation systems. However, LBE is also known as a highly corrosive with structural materials. In this paper, technological developments to overcome the issue, the latest research activities such as hightemperature operation and oxygen concentration control to ensure corrosion resistance, are introduced together with the outline of the target for ADS.
Sasa, Toshinobu; Saito, Shigeru; Obayashi, Hironari; Ariyoshi, Gen
JPS Conference Proceedings (Internet), 33, p.011051_1 - 011051_6, 2021/03
To realize Accelerator-driven system (ADS) for minor actinide transmutation, JAEA proposes to construct the Proton Irradiation Facility in J-PARC. The facility is planned to solve technical issues for safe application of Lead-bismuth Eutectic Alloy (LBE). The 250 kW LBE spallation target will be located in the facility to prepare material irradiation database by both proton and neutron irradiation in the temperature range for typical LBE-cooled ADS. Various studies for important technologies required to build the facilities are investigated such as oxygen concentration control, instruments development, remote handling techniques for target maintenance, and spallation target design. The large scale LBE loops for mock up the 250 kW LBE spallation target and material corrosion studies are also manufactured and applied to various experiments. The latest status of 250 kW LBE spallation target design works will be summarized.
Saito, Shigeru; Okubo, Nariaki; Obayashi, Hironari; Wan, T.; Sugawara, Takanori; Sasa, Toshinobu; Maekawa, Fujio
JPS Conference Proceedings (Internet), 28, p.071003_1 - 071003_6, 2020/02
Japan Atomic Energy Agency (JAEA) proposes transmutation of minor actinides (MA) by accelerator-driven systems (ADS). The ADS designed by JAEA is a system composed by LBE (Lead-Bismuth Eutectic) spallation target and a subcritical core. In the ADS, a beam window (BW) is exposed in complex field of heavy irradiation by proton/neutron and corrosion by flowing LBE. To develop ADS structural materials, it is of critical importance to investigate materials used in such environment. Thus, JAEA plans to construct a proton irradiation facility at the J-PARC to prepare an irradiation database for candidate ADS structural materials and to investigate irradiation effects in flowing LBE environment. In this paper, giving a whole scope of the JAEA ADS development, some results of experimental measurements and the specific program for planed R&D will be presented.
Futakawa, Masatoshi
IOP Conference Series; Materials Science and Engineering, 74(1), p.012001_1 - 012001_7, 2015/02
Times Cited Count：2 Percentile：65.6(Materials Science, Multidisciplinary)Innovative researches using neutrons are being performed at the Materials and Life Science Experimental Facility, MLF, at the Japan Proton Accelerator Research Complex, J-PARC, in which a mercury target system is installed for MW-class pulse spallation neutron sources. The structural materials of the mercury target are subjected to irradiation damage due to protons and neutrons, very high cycle fatigue damages due to repeated pressure waves caused by the proton beam bombardment in mercury and so-called liquid metal embrittlement. That is, the structural materials must be said to be exposed to the extremely severe environments. In the paper, research and development relating to the material issues in the high power spallation neutron sources that has been performed so far at J-PARC is summarized.
Saito, Shigeru; Tsujimoto, Kazufumi; Kikuchi, Kenji; Kurata, Yuji; Sasa, Toshinobu; Umeno, Makoto*; Nishihara, Kenji; Mizumoto, Motoharu; Ouchi, Nobuo; Takei, Hayanori; et al.
Nuclear Instruments and Methods in Physics Research A, 562(2), p.646 - 649, 2006/06
Times Cited Count：25 Percentile：83.96(Instruments & Instrumentation)JAERI is conducting R&D on the Accelerator Driven System (ADS) to transmute minor actinides (MAs) contained in the high-level radioactive waste under the OMEGA (Options Making Extra Gains from Actinides and fission products) program. The present study discusses the design of the ADS plant and various R&D on the ADS. The reference design of ADS plant in JAERI is the 800 MWth, Pb-Bi eutectic (LBE) cooled, tank-type subcritical reactor loaded with (MA+Pu) nitride fuel. LBE is selected as a spallation target material. In our results of the optimization study on the neutronics of the ADS, we have adopted the maximum multiplication factor (k
) of 0.97. From the results of the thermal-hydraulic analysis around the LBE spallation target, partition wall and flow control nozzle are required to keep the structural integrity around the core and the beam window. Feasibility of beam window was also discussed for transient conditions of proton beam.
Saito, Shigeru; Kikuchi, Kenji; Usami, Koji; Ishikawa, Akiyoshi; Nishino, Yasuharu; Kawai, Masayoshi*; Dai, Y.*
Journal of Nuclear Materials, 343(1-3), p.253 - 261, 2005/08
Times Cited Count：9 Percentile：53.19(Materials Science, Multidisciplinary)A beam window of a spallation target will be subjected to proton/neutron irradiation, pressure wave and thermal stresses accompanied by high-energy proton beam injection. To obtain the irradiation data, the SINQ target irradiation program (STIP) was initiated in 1996 at Paul Scherrer Institute (PSI) and has been progressing. JAERI takes part in STIP and shares the PIE work. In this study, the results of tensile tests on austenitic stainless steels, JPCA and 316F SS, will be reported. The results indicate that the irradiation causes considerable hardening and degradation of ductility. The YS increases in this study are slightly large in comparison with those irradiated at fission reactor. Strain-to-necking (STN) values show sufficient large ductility of the irradiated JPCA-SA and 316F-SA. The trends of the STN decrease in this study are slightly abrupt in comparison with those irradiated at fission reactor. All specimens, including irradiated at embrittlement temperature for austenitic steels, fractured in ductile manner.
Sasa, Toshinobu; Umeno, Makoto*; Mizubayashi, Hiroshi*; Mori, Keijiro*; Futakawa, Masatoshi; Saito, Shigeru; Kai, Tetsuya; Nakai, Kimikazu*; Zako, Akira*; Kasahara, Yoshiyuki*; et al.
JAERI-Tech 2005-021, 114 Pages, 2005/03
JAERI-Tech-2005-021.pdf:9.66MB
To perform the research and development for accelerator-driven system (ADS), Japan Atomic Energy Research Institute (JAERI) plans to build a Transmutation Experimental Facility under the JAERI-KEK joint J-PARC program. Transmutation Experimental Facility consists of two buildings, Transmutation Physics Experimental Facility to make reactor physics experiment with subcritical core, and ADS Target Test Facility for the preparation of irradiation database for various structural materials. In this report, purpose to build, experimental schedule, and design study of the ADS target test facility with drawer type spallation target are summarized.
Saito, Shigeru; Kikuchi, Kenji; Usami, Koji; Ishikawa, Akiyoshi; Nishino, Yasuharu; Kawai, Masayoshi*; Dai, Y.*
Journal of Nuclear Materials, 329-333(Part1), p.1093 - 1097, 2004/08
Times Cited Count：6 Percentile：40.72(Materials Science, Multidisciplinary)In several institutes, research and development for an accelerator-driven spallation neutron source have been progressed. A beam window of a target will be subjected to proton/neutron irradiation, pressure wave and thermal stresses accompanied by high-energy proton beam injection. To obtain the irradiation data, the SINQ target irradiation program (STIP) at Paul Scherrer Institute (PSI) has been progressing. JAERI takes part in STIP and shares the PIE work. The STIP specimens are very small so that we developed a new fatigue-testing machine with ceramic piezoelectric actuator. The results showed that the numbers of cycles to failure (Nf) on the irradiated specimens were less than that of unirradiated specimens. Dpa dependence of Nf was not clearly seen in the irradiation conditions. On the other hand, fracture surface varied with irradiation conditions. Specimens irradiated at low temperature fractured in ductile manner. However, interglanular fractured surface was observed for 316F SS irradiated up to 12.5 dpa at 360C.
Sato, Hiroshi; Aso, Tomokazu; Kogawa, Hiroyuki; Teshigawara, Makoto; Hino, Ryutaro
JAERI-Tech 2004-018, 23 Pages, 2004/03
JAERI-Tech-2004-018.pdf:2.42MB
The Japan Atomic Energy Research Institute is constructing a mega-watt class spallation neutron source in cooperation with the High Energy Accelerator Research Organization. A cold moderator using liquid hydrogen is one of the key components in the system, which directly affects the neutronic performance both in intensity and pulse time structure. Since a hydrogen temperature rise in the moderator vessel affects the neutronic performance, it is necessary to suppress the recirculation and stagnant regions which would cause hot spots. A cold moderator with a poison plate (poisoned decoupled moderator) has a high possibility to generate the stagnant region on and near the poison plate. Thermal-hydraulic analyses were carried out with proposed inner structure of the poisoned cold moderator. The stagnant and recirculation regions could be reduced by making a gap between the poison plate end and the vessel bottom surface, and the local temperature rise also could be kept under the required design value.
Sasa, Toshinobu; Oigawa, Hiroyuki; Tayama, Ryuichi*; Hayashi, Katsumi*
Journal of Nuclear Science and Technology, 41(Suppl.4), p.30 - 33, 2004/03
The construction of Transmutation Experimental Facility (TEF) is planned under the framework of Japan Proton Accelerator Research Complex (J-PARC) project. A liquid lead-bismuth (Pb-Bi) spallation target with beam power of 600MeV-200kW will be installed into the TEF. Analyses were performed to determine the effective thickness of biological shield for Pb-Bi target by using both MCNPX and ATRAS code system. Thickness of around 6m should be required to decrease the radiation level. The streaming analyses through the proton injection beam duct and the primary cooling circuit piping were also performed. The result of the beam duct streaming shows good agreement between the results of MCNPX and DUCT-III. The additional shield must be installed to suppress the activation of accelerator components. In the case of streaming through the primary cooling circuit piping, it is proved that the radiation level at the exit of the shield is allowable. The radiation level can be much more reduced by optimizing the bending position and length of the piping.
Kinoshita, Hidetaka; Haga, Katsuhiro; Kogawa, Hiroyuki; Kaminaga, Masanori; Hino, Ryutaro
Proceedings of ICANS-XVI, Volume 3, p.1305 - 1314, 2003/07
The JAERI and the KEK are promoting a plan to construct the spallation neutron source at the Tokai Research Establishment, JAERI, under J-PARC project. A mercury circulation system has been designed so as to supply mercury to the target stably. Conceptual design is almost finished. But, it was necessary to confirm a mercury pump performance, and more, to investigate erosion rate under the mercury flow as well as an amount of mercury remained on the surface after drain. The mercury pump performance was tested under the mercury flow conditions by using an experimental gear pump, which had almost the same structure as a practical mercury pump to be expected, and the erosion rates in a mercury pipeline as were investigated. The discharged flow rates of the gear pump increased linearly with the rotation speed. Erosion rates obtained under the mercury velocity less than 1.6 m/s was found to be so small. For the amount of remaining mercury on the pipeline, radioactivity of this remaining mercury volume was found to be three-order lower than that of the target casing.
Kawai, Masayoshi*; Li, J.*; Watanabe, Ryuzo*; Kurishita, Hiroaki*; Kikuchi, Kenji; Igarashi, Tadashi*; Kato, Masahiro*
Dai-23-Kai Nihon Netsu Bussei Shimpojiumu Koen Rombunshu, p.313 - 315, 2002/11
The objective of the present study is to develop the stainless-steel-bonded tungsten alloys by powder metallurgy processes. Commercially available tungsten powders and stainless steel (SUS304L) powder were used as the raw materials and mixed by ball milling at the ratios of 97mass% W -3% SUS and 93mass% W -7mass% SUS. Powder compacts were formed by die pressing and cold isostatic pressing (CIP), then sintered mainly in vacuum at the temperatures above the melting point of the stainless steel phase. Some samples were fabricated by glass-encapsulated hot isostatic pressing (HIPing) at lower temperatures. The microstructural observation was made by scanning electron microscopy (SEM). The thermal properties of the produced alloy and various tungsten materials supplied from Allied Material Corp. was measured with the laser-frash method. It was found that stable liquid-phase-sintered microstructures were not easily formed in the tungsten-stainless steel system. The electron probe microanalysis (EPMA) revealed that tungsten was considerably dissolved in the stainless steel phase during sintering. Therefore, thermal conductivity of the W/7 mass% SUS alloy was 22.8-53.5 W/m/K that was very lower than theoretical value calculated from those of pure tungsten and stainless steel. Its temperature dependence is resembled to that of stainless steel, i.e., thermal conductivity increased with the specimen temperature as like stainless steel. The diffusivity of pure tungsten is compared with those of tungsten alloys.
Oigawa, Hiroyuki
Nihon Butsuri Gakkai-Shi, 56(10), p.749 - 754, 2001/11
no abstracts in English
Aso, Tomokazu; Kaminaga, Masanori; Terada, Atsuhiko*; Hino, Ryutaro
Nihon Genshiryoku Gakkai-Shi, 43(11), p.1149 - 1158, 2001/11
Times Cited Count：0 Percentile：0.01(Nuclear Science & Technology)no abstracts in English
Sasa, Toshinobu; Saito, Shigeru; Kikuchi, Kenji; Kurata, Yuji; Futakawa, Masatoshi
Transactions of the American Nuclear Society, 85, p.299 - 300, 2001/11
Study of liquid lead-bismuth (Pb-Bi) technology is performed at JAERI. Pb-Bi cooled ADS has favorite neutronic performances rather than that of sodium-cooled ADS. In order to develop an ADS, JAERI has proposed a transmutation experimental facility which consists of a 600 MeV-200 kW Pb-Bi spallation target and a fast critical assembly with a spallation target within a framework of the high intensity proton accelerator project. In the viewpoint of engineering application of Pb-Bi, there is a key technology, which should be proven before the construction of TEF. They are materials issues and handling techniques of flowing eutectic Pb-Bi. To control these technical issues, we proceed two experimental studies with the material corrosion test device and the liquid Pb-Bi loop.
Kinoshita, Hidetaka; Kaminaga, Masanori; Hino, Ryutaro
JAERI-Tech 2001-052, 41 Pages, 2001/08
JAERI-Tech-2001-052.pdf:1.99MB
no abstracts in English
Aso, Tomokazu; Kaminaga, Masanori; Terada, Atsuhiko*; Hino, Ryutaro
JAERI-Tech 2001-051, 22 Pages, 2001/08
JAERI-Tech-2001-051.pdf:4.51MB
no abstracts in English
Islam, M. S.*; Terada, Atsuhiko*; Kinoshita, Hidetaka; Hino, Ryutaro; Monde, Masanori*
JAERI-Tech 2001-044, 49 Pages, 2001/07
JAERI-Tech-2001-044.pdf:2.49MB
no abstracts in English
Kawai, Masayoshi*; Kikuchi, Kenji; Kurishita, Hiroaki*; Li, J.*; Furusaka, Michihiro*
Journal of Nuclear Materials, 296(1-3), p.312 - 320, 2001/07
Times Cited Count：47 Percentile：93.85(Materials Science, Multidisciplinary)no abstracts in English
